Question

Data for 34 cereals were examined to look for an association between fiber content and calories. A regression analysis was performed, in which the dependent variable was fiber and the independent variable was calories. Given below are graphs from the regression output. Which of the assumptions for inference are violated? Explain Click the icon to view the graphs from the regression output. Regression output graphs Is the straight enough condition satisfied? Yes 0 12 Is the independence assumption satisfied? Yes O No 0 1 2 3 4 Predicted (g) 50 75 100 125 150 Is the equal variance assumption satisfied? ○ No Yes Is the nearly Normal condition satisfied? ○ No Yes -50510 Residuals PrintDone

Answer 1

Yes, From the figure 1 the straight enough condition is satisfied so that we can build a linear model.

No ,Since the residuals do not shows a random patterm, the errors are not independent

No, The residuals do not form a "horizontal band" around the 0 line. This suggests that the variances of the error terms are equal.

The normality condition is not satisfied, the graph shown in the 3rd figure is positively skewed.